Add ExceptionHandler to ModuleSystem, remove heap allocated v8::TryCatch.

chrome/renderer/extensions/module_system.h

Index: chrome/renderer/extensions/module_system.h
diff --git a/chrome/renderer/extensions/module_system.h b/chrome/renderer/extensions/module_system.h
index e371865d9cacfb3f560d4fe5cbf0c71786fd1916..4f790842aec9f0a5095e355b90c10a2d991a837b 100644
--- a/chrome/renderer/extensions/module_system.h
+++ b/chrome/renderer/extensions/module_system.h
@@ -37,10 +37,17 @@ class ModuleSystem : public NativeHandler {
  public:
   class SourceMap {
    public:
+    virtual ~SourceMap() {}
     virtual v8::Handle<v8::Value> GetSource(const std::string& name) = 0;
     virtual bool Contains(const std::string& name) = 0;
   };
 
+  class ExceptionHandler {
+   public:
+    virtual ~ExceptionHandler() {}
+    virtual void HandleUncaughtException() = 0;
+  };
+
   // Enables native bindings for the duration of its lifetime.
   class NativesEnabledScope {
    public:
@@ -99,9 +106,16 @@ class ModuleSystem : public NativeHandler {
                     const std::string& module_name,
                     const std::string& module_field);
 
+  void set_exception_handler(scoped_ptr<ExceptionHandler> handler) {
+    exception_handler_ = handler.Pass();
+  }
+
  private:
   typedef std::map<std::string, linked_ptr<NativeHandler> > NativeHandlerMap;
 
+  // Called when an exception is thrown but not caught.
+  void HandleException(const v8::TryCatch& try_catch);
+
   // Ensure that require_ has been evaluated from require.js.
   void EnsureRequireLoaded();
 
@@ -139,6 +153,9 @@ class ModuleSystem : public NativeHandler {
   // pinned natives as enabled.
   int natives_enabled_;
 
+  // Called when an exception is thrown but not caught in JS.
+  scoped_ptr<ExceptionHandler> exception_handler_;
+
   std::set<std::string> overridden_native_handlers_;
 
   DISALLOW_COPY_AND_ASSIGN(ModuleSystem);